Occam, possibly (but just that) a well trained professional pilot, but not the amateur who supposedly flew Flight 77 who a few short weeks earlier was denied rental of a single engine Cessna at the Bowie Md airport due to his complete lack of piloting skills.

There have been lots of airplane crashes, including some airliners that crashed into buildings.

Never has there been one that was swallowed by a hole far smaller than the plane itself, and in such cases, parts (large and small) of the plane, fuselage, tail, luggage, seats, etc. were found.